Cross feeding mechanism for grinding machines



Oct. 3, 1933- p PLANTlNGA 1,929,214

CROSS FEEDING MECHANISM FOR GRINDING MACHINES Filed Sept. 30, 1930 2 Sheets-Sheet @Mrwy.

1933- P. PLANTINGA ,9

CROSS FEEDING MECHANISM FOR GRINDING MACHINES Filed Sept. 30, 1930 2 Sheets-Sheet 2 Patented Oct. 3, 1933 V UNITED STATES onoss FElZDING MECHANISM Fon GRINDING MACHINES Peter Plantinga, Greenfield, Mass., assignor to Greenfield Tap & Die Corporation, Greenfield, Mass., a corporation of Massachusetts Application September so, 1930 7 Serial No. 485,472

8 Claims. (Cl. 51-165) This invention'relates to cross feeding. mechanism used in a grinding machine. In this general type of cross feeding mechanism, means is provided for automatically controlling-the rate and extent of cross feed during a grinding operation.

It is the object of my invention to improve the construction of such cross feed mechanism by providing means by which the feeding mecha-. nism may be adjusted manually to compensate for the wear of the wheel, or for other purposes. I also provide means by which this predetermined wheel adjustment may be varied to su' grinding conditions. My invention further relates to arrangements and combinations of parts which will. be hereinafter described and more particularly pointed out in the appended claims. I A preferred form of theinvention the drawings, in which is shown in 1 :01 Fig- 1 is a front elevation of parts of a grinding machine embodying my improvements;

Fig. 2 is a sectional side elevation, taken along the line 2-2 inFig. 1; l a .Figs. 3 and 4 are detail sectional elevations, 251 taken alongthe lines 33 and 4-'4 in Fig. 1,

respectively, and. 1

Fig. 5 is a detail-front elevation of certain feeding mechanism. I Referring particularly to Fig. 2,-1 have shown a 30; portionof a cross feed shaft Ill-mounted to vrotate in an anti-frictionbearing 11. A disc 12 is keyed to the shaft 10.;and its outer edge portion is provided with teeth and forms a :gear 13. A ratchet wheel 14 is mounted on a supporting structure 15 projecting laterally from the disc 12 andrigidlysecured thereto. Pawls 16 and 17 are positioned to engage the. teeth; of the ratchet wheel 14 and these pawls are intermittently actuated to advance the ratchet wheel 14 and cross feed shaft 10.

the pawls '16and'1 7 are'mounted. Asthe for ward limit 'of'movement of the pawls is constant, 55 the cam 20 effectively varies the feed by control- The extent. of movement of the wheel 14 for ling the rearward movement of the pawls. A

shield eventually comes into position under the feed pawls 16 and 17 and prevents any fur ther feeding movement.

The mechanism thus far described is of a well known commercial form and reference is made to the copending application of Alden M. Drake,

Serial No. 197,459, filed June 8, 1927, for a more detailed description.

The cam ring 20 is secured to the side of a hand wheel (Fig. 2) which is loosely rotatable about the axis of the cross feed shaft 10 A pinion 32 is mounted in a sleeve 33 rotatable-in a bearing member 34 mounted on the hand wheel 30. A disc or collar 35 is secured tothesleeve 33 and is provided with recesses 36 positioned for engagement by the end of a spring-pressed plunger 37, slidably mounted in a portion 38 of the bearing member 34.

The member 34 also has an enlarged or flange portion 40 provided with a circumferential recess 41 of L-shaped section and the flange portion 40 of the member 34 is secured to the hand wheel 30 by clamping screws 42. V

The pinion 32 is thus held from accidental rotation in the bearing 34 and forms a locking connection between the hand wheel 30 and the gear 13. It should be carefully noted'that the gear 13 is fixed in its angular relation. to the ratchet wheel 14 and that the cam ring 20 is fixed in its angular relation to the hand wheel 30.

In grinding internal work, the greater part of the wheel wear occurs during the roughing operation and it is desirable to compensate for, this wheel Wear by so adjusting the feeding mechanism that the wheel will be advanced in amount 7 corresponding to the wheelwear before the wheel truing operation. This compensating advance movement is commonly only a few thousandths of an inch and the amount variesaccording to the sizeand hardness-of the wheel and the amount of the roughing cut.

My present invention relates particularly to means for limiting thisslight additional feed to a predetermined amount, which amountm ay, however, be easily varied to suit different operating conditions.

For thispurposeI provide a member 50 (Figs.

. 1 and 2) freely rotatable about the axis of the sleeve 33 and having a handle 51 by which itmay be conveniently turned. 1 A contact plate 52 is secured to the handle 51 in position for engage ment by stops 53 and 54, secured inthe L-shaped recess 41 of' the flange 40. ,The stop53 is designed toremain in fixed position in the flange 40 and comprises a stud (Fig. 4) having an L-shaped head 55 and threaded to receive a clamping nut 56. The stop 53 is thus clamped in fixed position in the flange 41, which in turn is fixed to the hand wheel 30. I

The construction of the stop 54 is best shown in the upper part of Fig. 2. The stop'54 comprises a sleeve slidably mounted on astud 60 threaded into an L-shaped block 61 slidablein the recess 41 of the disc 40. A spring 62 holds the inner end of the sleeve seated, in one of a series of recesses 66 (Fig. 1) formed in the outer face of the flange 40. By pulling the sleeve outward, the sleeve and stud may be shifted from one recess 66 to another to thereby increase or diminish the separation of the adjustable stop 54 from the fixed stop 53. The handle member 50 previously described is provided with a stud 68 (Fig. 2) on which a pawl 69 is pivoted. A

53 to the adjustable stop 54 and a predetermined relative angular adjustment of the cam ring and ratchet wheel is thus effected. V

If a finer relative adjustment is desired, the stop 54 is moved to one of the other recesses 66,

thus further limiting the swinging movement of the handle 50.

The operator is thus able to effect an adjustment of the feeding mechanism to compensate for the wheel wear during the preliminary or rough-grinding operation and he" accomplishes this adjustment by merely swinging the handle 51 as far as is permitted by the stop 54,-thus turning the'pinion 32 a definite and predetermined distance, which distance may be readily varied and adjusted to suit operating conditions.

"It is sometimes desirable to adjust the cam ring 20 independently of the usual advance movements above described, and for this purpose a knob or thumb-nutis 'slidably mounted on the outer end of the sleeve 33 and is pushed yieldingly outward by a spring 81. The thumb nut 80 is secured in fixed angular relation to the ratchet wheel 71 by a stud 82 fixed in the ratchet wheel and extending through an opening 83 in a cam disc 84, formed on the inner end of the thumb nut 80. The cam'disc 84 is so proportioned that when the nut 80 is moved inward, the edge of the disc 84 will engage a stud 85 (Fig. 3) in the side of the feed pawl 69 and will raise the feed pawl to inoperative position. The pinion 32 may then be turned in either direction by the thumb nut 80.

The recesses 36 in the disc 35 are preferably equal in number to the recesses 66 in the flange 40 and are equally spaced angularly.

I have thus provided improved means by which the hand wheel 30 and cam wheel 20 may be adjusted a predetermined amount relative to the gear 13 and ratchet wheel 14, which predetere mined amount may be easily varied. I have also provided improved means by which the predetermined feeding means may be rendered inoperative and by which the parts may be adjusted manually in either direction to any desired extent by the thumb nut 80.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth'in the claims, but What I claim is:

1. In a cross feeding mechanism, a ratchet 80 wheel, a pawl mechanism for said wheel, a cam plate rotatable with said ratchet wheel and positivelyconnected to said ratchet wheel during the entire cross feeding operation, said cam plate controlling the pawl feeding action and deter- 85 mining different rates of feed during a continued cross feeding operation, manual means to change the angular relation of said cam plate to said ratchet wheel, and means to predetermine and positively limit the'extent of such change in angular relation produced by a single actuation of said manual means.

2. In a cross feeding mechanism, a ratchet wheel, a pawl mechanism for said wheel, a cam plate rotatable with said ratchet wheel and positively: connected tosaid ratchet wheel during the entire cross feeding operation, said cam plate controlling the pawl feeding action and determining different rates of feed during a continued cross feeding operation, manual means to change the angular relation of said cam plate to said ratchet wheel, and means to predetermine and positively limit the extent of such change in angular relation produced by a single actuation of said manual means, said limiting means being selectively adjustable.

3. In a cross feeding .mechanism, a ratchet Wheel, a pawl mechanism for said wheel, a cam plate rotatable with said ratchet wheel and con trolling the pawl" feeding action, a hand Wheel concentricwithsaid ratchet wheel andv on which said cam plate is mounted, a gear fixed to said ratchet wheel and concentric. therewith, a pinion mounted on said hand wheel at one side of the axis thereof and engaging said gear, a handle loosely mounted for angular movement on said hand wheel concentric with said pinion, an actuating connection between said handle and said pinion, and means to limit such angular movement of said handle to a predetermined amount.

4. The combination in a crossfeeding mechanism as set forth in claim 3 in which the actuating connection between the handle and pinion is operative in one direction only.

5. The combination in a cross feeding mechaanism as set forth in claim 3 in which the actuating connection comprises a ratchet wheel on the pinion and a pawl on the handle cooperating with said ratchet wheel.

-6. The combination in a cross feeding mechanism as set forth in claim 3 in which the handle engages'a fixed stop at the end of its return movement and an adjustable stop at the end of the pinion-feeding movement.

'7. The combination in a cross feeding mechanism as set forth in claim 3, in which a disc is fixed to said hand wheel concentric with said handle and having a circumferential recess therein, and in which astop stud is adjustable along said recess, and means is provided to secure said stud in selected positions.

'8. The combination in a crossfeeding mechaanism as set forth in claim 3, in which a disc is fixed to said hand wheel concentric with said handle and'ha'vin'g a circumferential recess therein,'and in which a stop stud is adjustablealong said recess, and means is provided to secure said stud in predetermined selected positions.

. PETER PLANTINGA. 

